ABSTRACT Alavesia has been known on the basis of five species in Late Cretaceous amber from Spain and Myanmar and two extant species from Namibia. Very recently, another extant species has been found in southern Brazil. Here we present a surprising diversity of Alavesia flies from the mid-Cretaceous of Myanmar (Late Albian-Early Cenomanian, ca. 99 Ma), including nine new species: A. angusta, sp. nov., A. brevipennae, sp. nov., A. lanceolata, sp. nov., A. latala, sp. nov., A. longicornuta, sp. nov., A. magna, sp. nov., A. pankowskiorum, sp. nov., A. spinosa, sp. nov., and A. zigrasi, sp. nov. The following new synonymy is proposed: Neoalavesia Poinar and Vega, 2020 = Alavesia Waters and Arillo, 1999. Notes are provided on an unusual structure, leg furrows found on femora to varying degrees among species, sometimes on tibiae, as well as notes on swarming behavior. Alavesia has undergone extensive extinction, a finding that further supports the relict nature of this genus and helps to explain the distribution of the other four Recent genera of Atelestidae, found in south and north temperate regions. Relict arthropod taxa preserved in Burmese amber are briefly reviewed, which also are narrowly endemic to temperate regions today.

中文翻译：

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Relict Genus Alavesia Waters 和 Arillo（双翅目：Empidoidea：Atelestidae）的白垩纪多样性

摘要 Alavesia 已知基于来自西班牙和缅甸的晚白垩世琥珀中的五种物种以及来自纳米比亚的两种现存物种。最近，在巴西南部发现了另一种现存的物种。在这里，我们展示了来自缅甸白垩纪中期（阿尔比安晚期 - 塞诺曼纪早期，约 99 Ma）的阿拉维斯果蝇的惊人多样性，包括九个新物种：A. angusta，sp。nov., A. brevenennae, sp. nov., A. lanceolata, sp. nov., A. latala, sp. nov., A. longicornuta, sp. nov., A. magna, sp. 十一月，A. pankowskiorum，sp。nov., A. spinosa, sp. 11 月，和 A. zigrasi，sp。十一月 提出了以下新的同义词： Neoalavesia Poinar 和 Vega，2020 = Alavesia Waters 和 Arillo，1999。 提供了关于一个不寻常的结构的注释，在不同物种的股骨上发现了不同程度的腿沟，有时在胫骨上，以及关于蜂拥行为的注释。Alavesia 经历了广泛的灭绝，这一发现进一步支持了该属的遗存性质，并有助于解释在南温带和北温带地区发现的其他四个新近属 Atelestidae 的分布。简要回顾了保存在缅甸琥珀中的残存节肢动物分类群，这些分类群今天也仅是温带地区的特有种。